It is not likely that just one of these factors alone is the issue,
but a variable mix of them all, thus referred to as having a 'personality', or unpredictable change from day to day.

It is easy to remedy once you see which are the offending factors.
One thing is is not, is the stove. It plays no role, other than it is a cold mass of 450 lbs, and needs a good amount of dry kindling to warm up and get the air moving.